Process of manufacturing incandescent mantles.



Human STATES PATENT onnlon.

ARTHUR MULLER, OF FURSTENWALDE-ON-THE-SPREE, GERMANY, ASSIGNOR TO THE FIRM OF-G. I. DROSSBACH & CO.

, OF FREIBERG, GERMANY.

PROCESS OF MANUFACTURING INOANDESOENT MANTLES.

No. 927,374. Specification a Letters Patent. Patented July 6, 1909.

Application filed October 4, 1907. Serial No. 395,895.

To all vwhom it may concern: I

Be it known that I, ARTHUR Mi'ILLER, a subject of the Emperor of Austria-Hungary,

residing at Flirstenwalde-0n-the-S rec, in the ties the fabrics have hitherto always been saturated with erystalloidal'solutions of salts (nitrates) of the rare earths em loyed which on reduction of the fabric to as by heating to incandescence leave the corresponding oxids. According to my-new process, on the contrary, the fibers of any suitable nature, such; for instance, asvegetable fibers (cotton, linen, ramie) or artificial silk, are impregnated with a colloidal solution of the oxidhydrates, the latter being absorbed direct and retained. In the prior process the solution of the salts used is merely mechanically absorbed, so that the salts only adhere'superlicially to the fiber and can be wholly removed by boiling in water. According to my invent on, on the other hand, thereis formed, as m the d eing process, an insoluble,

firmly adhering a sorption-combination bea tween the steeped iiber-suhstance and the colloidal oxid-hydrates. The great advantageoi this method over the prior process is that by a single impregnation, without any subsequent treatment of the iibers, the earths are most intimatel incorporated, adhering firmly and uniformly. a

If an incandescent mantle impregnated according to the ordinary method and. not burned off, is immersed in water, the salts are randly and completely extrmited-from the fabric. If, lmwever, a mantle impregnated with colloidal solution and not burned oil is put in water, the fabric still retains considerable quantities of the impregnated earths.

The colloidalsolution thorium hydrate can be prepared in various ways. (1).'Ac-' cording to welldcnown methodsz' acting upon the solid oxid with mineral acids, or dialyses of dilute thorium nitrate solution toward pure water. (2). A simple manner of preparing colloidal thorium hydroxid solution is ased uponthe resolution (peptisation) of freshly precipitated gelatinousthorium oxid by means of small quantities of added thorium nitrate. For instance, from 100 gralhs of dry thorium nitrate the thorium hydroxid is precipitated by means of an alkali, the gelatinous precipitate then carefully washed on the filter to remove entirely the excess of the alkali and the salts, and the pure precipitate then distributed in a little water' and heated to boiling point. Hereu 'on an aqueous solution of 10.2 grams of dryt orium nitrate is added in small quantities and the liquid kept boiling. After about half an (hour the thorium hydrox'idwill have been converted into a clear, slightly bluish opalescent colloidal solution. actually colloidal can be readily determined That this solution is by its behavoir toward precipitants: small.

quantities of alkali, and of mineral acids, immediately throw down the colloidal dis-- solved thorium hydr oxid as an insoluble gelatinous precipitate. tion so obtainedthe necessary quantity of cerium nitrate is added and the solution then diluted for use, depending upon the desired degree of concentration of the impregnating fluids All the remaining operations in the manufiwture of the incandescent mantle can be conducted as ordinarily.

Having thus described my invention, what I claim as new is:

1. In the manufacture of incandescent mantles, in impregnating the fabric of the latter-with a colloidal solution of an oxidhydrate of a rare earth, substantially as described. Y

2. In the manufacture of incandescent mantles, in impregnating the fabric of the latter with a fluid containing a colloidal solution of an oxid hydrate" of a rare earth, substantially as described.

In testimony whereof I have signed my name to this specification in the two subscribing witnesses.

ARTHUR MULLER.

Witnesses PAuIQAnnon, )LAnn SIM N.

To the colloidal 'solu presence of t 

